51 replies to this topic

[NA Jimbo]

Hi people, I'm just about to order the following to try and work out if it is the piston rings responsible for my smoke at high revs.

http://cgi.ebay.co.u...INE...:1|294:50

Should this be ok/fit?

I've a couple of questions as to how to perform the test itself on the VX

1. I've read that you need to hold the throttle open whilst turning the engine - will the fly by wire throttle on the VX actually open fully if the engine hasn't actually fired?

2. What's the easiest way to disable the injectors - is there a fuse or connector which is simple to pull?

Thanks in advance.

[theolodian]

Yeah, should be fine. The throttle body should open enough. The easiest fuse to pull would be the fuel pump, don't know which one it is though. Just wear eye protection in case fuel spits out the other spark plug holes though. Don't overtighten anything, and keep track of which plug came from which cylinder. It always helps to match the condition of the plug to the readings that you get.

[mandarinvx]

Don't be tempted to overtighten it (on a 2.2) as the cylinder head could crack

[markv]

Overtightening is a bit issue. And this has to do with the thread on the spakplugs being tapered! I don't think (but difficult to judge from the ebay page) that this kit has a tapered adapter? Mark

[techieboy]

TIS suggests the following:

Use a compression pressure recorder with a rubber cone and a measuring range up to 40 bar.

[John Faulkner]

use a threaded gauge & make sure the non return valve is at the threaded end of the hose, not the gauge end. this will give you a more accurate reading as the gauge is not also reading whats in the rubber tube....

[Dunde]

use a threaded gauge & make sure the non return valve is at the threaded end of the hose, not the gauge end. this will give you a more accurate reading as the gauge is not also reading whats in the rubber tube....

Doesnt really matter i guess, comp should measued and compared from all 4 cylinders.

[N17VES]

What grade oil did you put in? If you put some expensive fully synthetic performance oil in, this could cause blue smoke at high rpm due to being too thin.

[NA Jimbo]

What grade oil did you put in?

If you put some expensive fully synthetic performance oil in, this could cause blue smoke at high rpm due to being too thin.

I just use halfords fully synth 5w40?

[Zoobeef]

5w40 should be ok so you can prob rule that out

[NA Jimbo]

Cheers for the answers so far people. So what's the consensus? If the tester just has a normal thread is going to be ok in terms of just getting a seal for the test or do I need to search for a tester with a tapered thread?

[slindborg]

when you say smokes at high revs, is it while revving, or at lift off? if it does it when you have the throttle planted then its hugely likely to be rings, if its at lift off its valve stem seals

[N17VES]

What grade oil did you put in?

If you put some expensive fully synthetic performance oil in, this could cause blue smoke at high rpm due to being too thin.

I just use halfords fully synth 5w40?

5w40 is thinner at lower temps. From memory vauxhall recommend 10w40 - personally I would probabaly of stuck with that.

You could even try slightly thicker than 10w40 to resolve your current problems.....

[Zoobeef]

What grade oil did you put in?

If you put some expensive fully synthetic performance oil in, this could cause blue smoke at high rpm due to being too thin.

I just use halfords fully synth 5w40?

5w40 is thinner at lower temps. From memory vauxhall recommend 10w40 - personally I would probabaly of stuck with that.

You could even try slightly thicker than 10w40 to resolve your current problems.....

It only gets thinner as it gets warmer tho so if it was smoking when cold it would only get worse once its warmed up so the either of those wouldn't change it. I would see the results of the compression test first

[NA Jimbo]

when you say smokes at high revs, is it while revving, or at lift off?

if it does it when you have the throttle planted then its hugely likely to be rings, if its at lift off its valve stem seals

It's only when the throttle is open. Only does it between about 5800 rpm and the redline. Clear at start up, after idling and between gear changes. Annoying thing is that this was the engine I put in at the end of last year which should have only done 38k which is why I was hoping
it isn't the rings.

[slindborg]

when you say smokes at high revs, is it while revving, or at lift off?

if it does it when you have the throttle planted then its hugely likely to be rings, if its at lift off its valve stem seals

It's only when the throttle is open. Only does it between about 5800 rpm and the redline. Clear at start up, after idling and between gear changes. Annoying thing is that this was the engine I put in at the end of last year which should have only done 38k which is why I was hoping
it isn't the rings.

rings can die at 10miles if not bedded in right... so to hope a part is fine at 38K is kinda irrelevant.


are the plugs oily?

[NA Jimbo]

[/quote] rings can die at 10miles if not bedded in right... so to hope a part is fine at 38K is kinda irrelevant. are the plugs oily? [/quote] I was going to take the plugs out once I've got a compression tester but I'm now more confused as to which one to get the smoking has only developed in the last few miles. I'd done 10k smoke free miles after changing the engine, can the rings just die like that?

[John Faulkner]

I was going to take the plugs out once I've got a compression tester but I'm now more confused as to which one to get

the smoking has only developed in the last few miles. I'd done 10k smoke free miles after changing the engine, can the rings just die like that?

just get a threaded compression tester, any should be fine. if your just checking that all the cylinders are the same, ignore my comment about the valve, it shouldn't make too much difference

i think the taper ones are a tapered rubber bung that you 'stuff' in the spark plug hole, rather than threading it in. for obvious reasons, you want a threaded one!

[Pidgeon]

I think you're chasing your tail with the compression test. The pistons have oil control rings and compression rings, so it is theoretically possible the oil control rings are shot, allowing oil up the bores, while the compression rings are doing their job. Another thought, there must be some compression, as the car works, so unless you have a benchmark engine, you will end up with four readings that don't mean a great deal. If you are burning oil it has to be from the bores or the valve seals (assuming N/A). It is rare for a specific 'fault' to develop, it is usually general mileage related wear. Not what you wanted to hear, but I would save your money on the comp tester.

[NA Jimbo]

I think you're chasing your tail with the compression test. The pistons have oil control rings and compression rings, so it is theoretically possible the oil control rings are shot, allowing oil up the bores, while the compression rings are doing their job.

Another thought, there must be some compression, as the car works, so unless you have a benchmark engine, you will end up with four readings that don't mean a great deal.

If you are burning oil it has to be from the bores or the valve seals (assuming N/A). It is rare for a specific 'fault' to develop, it is usually general mileage related wear. Not what you wanted to hear, but I would save your money on the comp tester.

Bearing in mind that the car only smokes just before the redline and at no other time would I be likely to cause loads more damage if I just continue to drive the car for the next few months and keep the revs under 5500 rpm??